package com.nicefish.web.controller;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.nicefish.web.utils.SessionConsts;
/**
 * 专门用来获取图片验证码
 * @author zhangxf10
 */
@Controller
@RequestMapping("/vcode")
public class VCodeImgController{
	private static Random random = new Random();

	private static String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";	//随机产生的字符串

	private static int width = 80;		//图片宽

	private static int height = 26;		//图片高

	private static int lineSize = 40;	//干扰线数量

	private static int stringNum = 4;	//随机产生字符数量

	@RequestMapping(value = "/getImg", method = RequestMethod.GET)
	public void getRandcode(HttpServletResponse response,HttpSession session) {
		//BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类
		BufferedImage image = new BufferedImage(width, height,BufferedImage.TYPE_INT_BGR);
		Graphics g = image.getGraphics();//产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
		g.fillRect(0, 0, width, height);
		g.setFont(new Font("Times New Roman", Font.ROMAN_BASELINE, 18));
		g.setColor(getRandColor(110, 133));
		
		//绘制干扰线
		for (int i = 0; i <= lineSize; i++) {
			drowLine(g);
		}
		
		//绘制随机字符
		String randomString = "";
		for (int i = 1; i <= stringNum; i++) {
			randomString = drowString(g, randomString, i);
		}
		
		session.setAttribute(SessionConsts.ImageVertifyCode, randomString);
		g.dispose();
		try {
			ImageIO.write(image, "JPEG", response.getOutputStream());
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	/**
	 * 获得字体
	 * @return
	 */
	private Font getFont() {
		return new Font("Fixedsys", Font.CENTER_BASELINE, 18);
	}

	/**
	 * 获得颜色
	 * @param fc
	 * @param bc
	 * @return
	 */
	private Color getRandColor(int fc, int bc) {
		if (fc > 255){
			fc = 255;			
		}
		if (bc > 255){			
			bc = 255;
		}
		int r = fc + random.nextInt(bc - fc - 16);
		int g = fc + random.nextInt(bc - fc - 14);
		int b = fc + random.nextInt(bc - fc - 18);
		return new Color(r, g, b);
	}
	
	/**
	 * 绘制字符串
	 * @param g
	 * @param randomString
	 * @param i
	 * @return
	 */
	private String drowString(Graphics g, String randomString, int i) {
		g.setFont(getFont());
		g.setColor(new Color(random.nextInt(101), random.nextInt(111), random.nextInt(121)));
		String rand = String.valueOf(getRandomString(random.nextInt(randString.length())));
		randomString += rand;
		g.translate(random.nextInt(3), random.nextInt(3));
		g.drawString(rand, 13 * i, 16);
		return randomString;
	}

	/**
	 * 绘制干扰线
	 * @param g
	 */
	private void drowLine(Graphics g) {
		int x = random.nextInt(width);
		int y = random.nextInt(height);
		int xl = random.nextInt(13);
		int yl = random.nextInt(15);
		g.drawLine(x, y, x + xl, y + yl);
	}

	/**
	 * 获取随机的字符
	 * @param num
	 * @return
	 */
	public String getRandomString(int num) {
		return String.valueOf(randString.charAt(num));
	}
}